An adjustable damping valve device comprising a pre-stage valve and a main stage valve is known from U.S. Pat. No. 9,310,810. Further, an emergency operation valve which occupies an emergency operation position during an outage of the power supply for an actuator of the damping valve device is connected in series with the pre-stage valve. At least one pressure relief valve which opens in the event of overpressure in a control space of the damping valve device and accordingly determines a maximum damping force setting is in turn connected in parallel with the emergency operation valve.
The at least one pressure relief valve is arranged in the emergency operation valve. Small pressure relief valves which can be screwed into the emergency operation valve, for example, can be provided for this purpose taking into account the required installation space. Pressure relief valves of this type are available as constructional units and are comparatively inexpensive. However, owing to the small constructional shape, they are comparatively sensitive to manufacturing tolerances, e.g., in the closing spring. While this problem can be compensated with an adjustable supporting surface for the closing spring, the realizable volume flows through an individual pressure relief valve are comparatively small. Consequently, a plurality of pressure relief valves must be provided, which increases expenditure on assembly.
It is thus an object of the present invention to provide a damping valve device in which a pressure relief valve for a damping valve device can have low expenditure on assembly and a comparatively large flow cross section.